This converter allows an ordinary AM car radio to receive WWV at 10 MHz. WWV transmits the precise time of day and the car is the most common place to need accurate time.
The oscillator may use either a crystal or a ceramic resonator at either 9 MHz or 11 MHz. WWV will appear at 1MHz on the AM radio dial. A slightly different frequency may be desired if there is a strong station near 1 MHz (1000 on the dial). A ceramic resonator will tune far enough to “dodge” a strong station. The coaxial connections may be made by cutting an antenna extension cable in half to obtain two “pig tails” as shown above. Solder the outer braid directly to the copper board. The relay may be a small 12 volt DIP style relay or a 5 volt relay with a suitable current limiting resistor. When power is applied to the circuit, the
relay closes, connecting the circuit to the radio and antenna.
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